From Pandemic to Endemic

Image: Wilfried Pohnke - Pixabay

March 11, 2020: The World Health Organization officially declared a global pandemic caused by COVID-19.

The pandemic word has been used a lot in the 2 years since. People referred to 2019 as a "pre-pandemic" time. We heard epidemic, outbreak, mandate and variant become part of the vocabulary.

Now, it's March 2022 and things seem to be getting back to some kind of normalcy, though COVID-19 is still here primarily as the Omicron variant. Maks are seen less often. States, cities, schools, restaurants and stores are lifting mandates in many places. And we are starting to hear the word "endemic" being used more often. But what is the difference between a pandemic and an endemic?

The word "endemic" comes from the Greek word endēmos, which means "in the population." For epidemiologists, this means that the disease is always present at a baseline level. It's not gone. There are cases. But unlike a pandemic or an epidemic, the illness has become more predictable.

An endemic also means that the disease will stay with us for a long time. Think about influenza. We get yearly flu shots. There are variants. People still get the flu and some get very sick and some of them will die. 

The CDC estimates that from October 1, 2021 through March 5, 2022 (flu season in the U.S.), there have been 2,700,000 – 4,500,000 flu illnesses, resulting in 1,200,000 – 2,000,000 flu medical visits and 26,000 – 54,000 flu hospitalizations.  1,500 – 4,500 flu deaths occurred in that period.

The fact that many Americans were still staying at home, traveling less, wearing masks and generally being more careful certainly brought down flu cases as well as COVID-19 cases. For comparison, during the 2017-2018 flu season there were 52,000 deaths from flu.

Is COVID-19 really an endemic now? Some say yes; some say no. WE are not able to really predict what will happen next with COVID-19. Whatever word you attach to our current state, people still need to protect themselves by getting vaccinated.

What about the terms "eliminated" and "eradicated?" Will those ever apply to COVID-19?

If a disease is "eliminated" (from a country) it means that there is no more transmission among its own population. In the U.S. and some European countries, that is the case with measles.

Even better is smallpox which has been eradicated, meaning zero transmission. The last naturally occurring case of smallpox was in 1977.

It is important that we don't treat COVID-19 in an increasingly casual way no matter what label is attached to it. Malaria is considered endemic in many countries, but the World Health Organization tallied 627,000 deaths from this mosquito-borne disease in 2020.